There seemed to be some confusion in this discussion, so I decided to do
some research on this, and here's what I found.

The official term for paper weight is "basis weight."  Here's a short
explanation from
http://www.jhoe.com/support-downloads/paper-weight-chart.asp

"Basis Weight: Basis weight is the standard measurement of an amount of
paper. For example, the basis weight of Bond is determined by the weight
of 500 sheets of 17"x22" paper (the parent size). If a ream of 17"x22"
paper weighs 20 pounds, this is called 20 lb. paper."

... and here's their  "paper weight conversion chart" in a
well-organized, printable format:
http://www.jhoe.com/images/downloads/pdf/paper_chart.PDF

To make better sense of it all, here's an article called, appropriately
enough, "Making Sense of Basis Weights."  
http://www.tappi.org/index.asp?pid=26849&bhcd2=1062174248

It includes the following interesting paragraph:
"The rest of the world, including England, which originally blessed us
with this system, has gone metric and uses grams per square meter as the
standard basis weight of all types paper and paperboard. Changing to gsm
would be a step in the right direction but old customs die hard."

I found a few weight conversion tables (lb / gsm), and this site has a
very informative page on "How to buy paper - Metric measurements"
http://www.papercatalog.com/HowtoBuy/chapter16.htm

The following paragraph from this site might be helpful for those who
like calculating things:
"Basic formula:  To convert from basis weight in pound to grams per
square meter, multiply the basis weight by 1406.13 and divide by the
square inches in the base sheet.  For example, to convert from 20 lb. 17" 
x 22"/500, multiply 20 lbs. by the constant 1406.13 and divide by 374 =
75 g/m2."

David Shatto
Los Angeles


On Fri, 29 Aug 2003 09:40:47 -0400 "Joseph B. Reid" wrote:

> Jan Saxton asked in USMA 26717:
> 
> >** Reply to note from "Bill Potts" <[EMAIL PROTECTED]> on Wed,
> 27 Aug 2003
> >18:43:55 -0700
> >
> >Does this mean that if I buy 8.5"x11" and 8.5"x14" paper of the same 
> quality
> >it'll have different weight labelling?  20 lb paper in letter size
> (quarto)
> >would be equivalent to about 25.5 lb in legal size (foolscap).
> >
> >Surely that can't be right?!
> >
> 
> I agree with Jan that it is not logical, but as I understand it, that 
> is the way it is.
> -- 
> Joseph B. Reid
> 17 Glebe Road West
> Toronto  M5P 1C8              Telephone 416-486-6071
> 

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